A known productive printing apparatus for printing on cut sheets comprises a printing station for applying an image on both sides of said cut sheet, a sheet input station for storing cut sheets to be printed, a sheet output station for collecting processed cut sheets and a sheet transport path arranged for advancing cut sheets throughout the printing apparatus. Said sheet transport path may be arranged for in a simplex printing mode selectively moving cut sheets from said sheet input station along the printing station, which prints a first image on the cut sheet, towards the sheet output station. Alternatively said sheet transport path may be arranged for in a duplex printing mode selectively after printing the first image circulating the cut sheet along a circulating duplex path back to the printing station for printing a second image on another side of the cut sheet opposite to the first image.
A sheet diverting unit may be arranged downstream of the printing station for selectively diverting a sheet towards a first receiving path, such as said circulating duplex path, or towards a second receiving path, such as an output path towards the sheet output station. The sheet diverting unit comprises an inlet path for advancing a sheet in a sheet supply direction towards a diverter. The diverter comprising a shaft, a deflector being connected to said shaft and extending between said shaft and a tip. Said actuator is arranged for rotating the shaft thereby selectively pivoting the deflector between a first deflector position for directing the sheet into the first receiving path and a second deflector position for directing the sheet into the second receiving path. The deflector comprises a curved edge and a guiding edge, said curved edge arranged facing a second trajectory to the second receiving path in the second deflector position for deflecting the sheet into the second receiving path and said guiding edge arranged facing a first trajectory to the first receiving path in the first deflector position for guiding the sheet into the first receiving path, such as a straight path or straight first trajectory arranged in line with inlet path.
To achieve higher productivity in printing cut sheets a demand exists for reducing a inter sheet gap (or free distance) between successive sheets advancing in the sheet transport path. Similar to the free distance a free distance time, which is a time between a trailing edge of an outgoing sheet and a leading edge of a subsequent sheet, may be reduced. As the free distance between successive sheets is reduced the diverter of the sheet diverting unit needs to switch faster between the first deflector position and the second deflector position. However faster switching, i.e. faster pivoting of the deflector, may lead to uncontrolled positioning of the deflector in the first deflector position and in the second deflector position. Furthermore the outgoing sheet may become damaged at a trailing edge by a fast switching deflector.